keep the tank running, i have heard (if i remember correctly) the ick should die out on it's own if there are no fish in the tank for the parasite to feed from within a month.
otherwise natural cures, ... turn the heat up in the tank, 84-86F should kill it within a few days (even if there are fish) pushes their metabolism past it's ability to survive
both would be a bonus to ensure your tank is safe.
easier than cleaning
boiling your water & sterilizing everything is ... you'll kill what you don't want, but you'll also kill what you do want.
if the tank has been empty for any period of time, great, ... if not, take the time to landscape, plant, keep it healthy till enough time has passed that the ich is guaranteed to have gone, ... after that get fish you want.
otherwise natural cures, ... turn the heat up in the tank, 84-86F should kill it within a few days (even if there are fish) pushes their metabolism past it's ability to survive
both would be a bonus to ensure your tank is safe.
easier than cleaning
boiling your water & sterilizing everything is ... you'll kill what you don't want, but you'll also kill what you do want.
if the tank has been empty for any period of time, great, ... if not, take the time to landscape, plant, keep it healthy till enough time has passed that the ich is guaranteed to have gone, ... after that get fish you want.